The Chinese government is investigating Microsoft for possible breaches of anti-monopoly laws, following a series of surprise visits to Redmond's offices in cities across China on Monday. These surprise visits were part of China's ongoing investigation [warning: WSJ paywall], and were based on security complaints about Microsoft's Windows operating system and Office productivity suite. Results from an earlier inspection apparently were not enough to clear Microsoft of suspicion of anti-competitive behavior. Microsoft's alleged anti-monopoly behavior is a criminal matter, so if found guilty, the software giant could face steep fines as well as other sanctions.